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A pair of intramolecular anodic olefin coupling reactions has been used to construct the arteannuin ring skeleton. Both coupling reactions took advantage of a furan ring as one of the coupling partners. In the first, it was found that an enol ether derived from an aldehyde was not an effective initiating group for the reaction. Instead, the cyclization benefited strongly from the use of a N,O-ketene acetal initiating group. In the second cyclization, an endocyclic enol ether was coupled to the furan ring. This second electrolysis reaction generated the key tetrasubstituted carbon at the center of the arteannuin ring skeleton.

The ability of intramolecular anodic olefin coupling reactions to form new carbon−carbon bonds has been shown to depend on the polarization of the intermediate radical cation rather than how electron-rich it is. A series of substrates was studied that allowed for a direct comparison of these two parameters. The successful cyclizations led to the formation of highly functionalized bicyclic molecules containing four contiguous stereogenic atoms, one of which was tetrasubstituted. For the first time, an ene diol ether derivative was shown to be compatible with the cyclization reaction.

Electrochemistry is a powerful tool for initiating new umpolung reactions. In this paper, two examples are provided. One demonstrates the use of electrochemistry for reversing the polarity of known functional groups and triggering carbon-carbon bond formation. The second demonstrates the use of electrochemistry for reversing the polarity of a chemical reagent, a technique that allows for spatially locating synthetic transformations on addressable chips.

Time-of-flight secondary ion mass spectrometry (TOF SIMS) has been used in conjunction with a mass spectrometry cleavable linker to determine the percent conversion of reactions that were conducted site-selectively on an addressable microelectrode array. When combined with fluorescence techniques for analysis of the reactions, the TOF SIMS experiment provides a means for optimization of both reaction confinement and reaction efficiency on the microelectrode arrays.

While anodic cyclizations have been shown to be compatible with the synthesis of lactones, the previous synthetic route to the starting materials was cumbersome and limited the overall utility of the approach. In this manuscript, a new strategy is reported that allows for very rapid synthesis of the electrolysis substrates. In addition, an efficient conversion of the ortho ester product obtained from the oxidative cyclization to a lactone acid is reported. The result is a dramatically improved synthetic strategy for the synthesis of functionalized tetrahydrofuranones.

A series of silyl-substituted amino acids have been synthesized, inserted into peptides, and then employed as precursors for oxidatively generating reactive N-acyliminium ions. Both electrochemical and chemical oxidation procedures have been employed. N-Acyliminium ion generation in a solid-phase substrate as well as application to a small library of functionalized dipeptides has been demonstrated. Limitations in terms of how electron-rich the silyl groups can be as well as the compatibility of multiple silyl groups within a longer peptide are defined.

Pd(0) was generated at preselected sites on an electrochemically addressable chip and then utilized to effect a Heck reaction. The Pd(0) was confined to the preselected electrodes with the use of allylmethyl carbonate. Unlike most mediated electrochemical reactions, the electrolysis in this case was not used to convert a stoichiometric process into a catalytic one by recycling the metal. Instead, the unique environment of the chip was used to interfere with a catalytic process to make it stoichiometric. This was done to gain spatial control over the reaction. The development of a strategy for conducting Pd(0)-catalyzed reactions on the chips should greatly expand the synthetic chemistry available for building chip-based libraries.

The chemical reactivity of radical cations derived from N,O-ketene acetals has been examined and compared with the reactivity of radical cations derived from both ketene dithioacetals and enol ethers. Synthetically, the N,O-ketene acetal radical cations lead to more efficient cyclization reactions than either the ketene dithioacetal or enol ether derived radical cations. Cyclic voltammetry experiments using allylsilane trapping groups show that the efficiency of these cyclizations is not due to the N,O-ketene acetal radical cations being more reactive but rather more stable to decomposition. Finally, cyclizations using chiral oxizolidinones were examined.

The feasibility of using active semiconductor chips containing addressable arrays of microelectrodes for the “real-time” monitoring of biologically relevant binding events has been demonstrated by detecting the binding of a coumarin substrate by an anticoumarin antibody. The coumarin substrate was synthesized proximal to predetermined electrodes on the chip with the use of a Pd(II) reagent that was itself generated by using the selected electrodes. Once the coumarin was synthesized, its binding to the anticoumarin antibody was detected by monitoring the current associated with a ferrocene−ferrocinium ion redox cycle that was established between the electrodes on the chip and a remote auxiliary electrode.